Background
National Cancer Data Base (NCDB) retrospective cohort analysis of treatment patterns and survival in vulvar squamous cell carcinoma. Examined associations between primary treatment modality (surgery alone, surgery + adjuvant RT, definitive RT, combined) and overall survival, focused on adjuvant RT in node-positive and margin-positive disease. Among the largest population-based vulvar cancer outcome studies.
Interventions and follow up
Treatment groups: Surgery alone; surgery + adjuvant RT ± concurrent chemo; definitive RT ± chemo; other combinations
Primary endpoint: Overall survival by treatment modality and disease characteristic
mFollow up: Database-linked (NCDB); median variable
Primary endpoint: Overall survival by treatment modality and disease characteristic
mFollow up: Database-linked (NCDB); median variable
Results
Adjuvant RT (LN+ or margin+): Improved OS vs surgery alone; HR ~0.7–0.8 in node-positive/close-margin patients
Definitive chemoRT vs RT alone: CRT improved OS in locally advanced disease (HR ~0.75, P<.05)
Treatment-volume effect: Higher-volume centers associated with superior OS
Definitive chemoRT vs RT alone: CRT improved OS in locally advanced disease (HR ~0.75, P<.05)
Treatment-volume effect: Higher-volume centers associated with superior OS
Adverse events
Main adverse events: Administrative database — no toxicity data; extrapolated from published series.
Conclusions
Population-level data confirm adjuvant RT is associated with improved survival in lymph node-positive and margin-positive vulvar cancer, supporting postoperative RT. Concurrent chemotherapy with RT in locally advanced disease is associated with additional survival benefit.
Key Limitations
NCDB limitations: no RT technique/dose, brachytherapy use, or specific chemo regimens. Selection bias (RT-selected patients differ systematically). No disease-specific survival endpoint. Potential coding errors. Adjuvant RT benefit concordant with randomized GOG 37.
Clinical Context
Corroborates randomized GOG 37 supporting adjuvant inguinofemoral-pelvic RT after surgery in LN-positive vulvar cancer, and provides population-level support for concurrent chemotherapy in locally advanced disease. ASCO/ESMO guidance recommends adjuvant RT ± concurrent cisplatin for LN-positive (≥2 LNs, ECE, bilateral nodes), positive/close margins, and advanced primary after surgery. Volume finding supports referral to specialized centers.